Alarm switch



Patented Aug. 28, 1923.

UNITED STATES PATRICK A. FBIEL, 0F

ALARM Application filed September To all whom it may concern:

Be it known that I, PATRICK A. FRIEL, a citizen of the United States, residin at Bayonne, in the county of Hudson and btate of New Jersey, have invented certain new and useful Improvements in Alarm Switches, of which the following is a specification.

This invention relates to automatic switches and has particular reference to electrical switches adapted 1particuarly for use in connection with signa s or alarm systems.

Among the objects of the invention is to rovide an automatic switch normally open lint adapted .to be automatically closed as a result of either a flow of Water throu h a pipe system, a change of level of a y ofl static water, or some other condition of the mechanism or means whereby the condition of a body of liquid is caused to change and thereby close the circuit.

More specifically stated one adaptation of the invention is in automatic sprinkler sys-v tems, commonly used in modern buildings, and in which there is provided a stand pipe filled with water under pressure, which water being normally static begins immediately to flow through the stand pipe as a result of the discharge of water at any one or more automatic sprinkler heads, and in which system it is intended for an indication or an alarm to be rendered at some distant point, such as in the ofiice of the superintendent, the insurance head quarters, or elsewhere, to establish the fact that there is a flow of water through said main pi and apparently a fire somewhere in t a building. In alarm systems heretofore generally used electrical switches have been employed in connection with the main stand pipe, but because'of leakage of water into the switches causing short circuiting, false alarms are given, causing a tremendous amount of trouble and even expense when said alarms are caused at night when the various departments of the building are locked and need to be broken into in the attempt to locate the supposed fire.

One of the specific ob]ects of the invention is to provide a switch attachment for a water pipe, the switch including a ravity medium which will act promptly an positively to close the circuit when the flow of water is initiated and which medium can by no means be disturbed by leakage of water.

Withthe foregoing and other objects in 1,466,431 PATENT OFFICE.

BAYONNE, NEW JERSEY.

SWITCH.

24, 1921. Serial No. 502,855.

view the invention consists in the arrangement and combination 'of parts hereinafter descr bed and claimed, and while the invention is not restricted to the exact details of constructlon disclosed or suggested herein, still for the purpose of illustrating a practical embodiment thereof reference is had to the accompanying drawings, in which like reference characters designate the same parts in the several views, and in which- F1 re 1 1s a vertical sectional view indicatlng a preferred embodiment of my invention applied to a stand pipe of an automat c sprinkler system or its equivalent.

Fig. 2 IS a vertical transverse sectional detail on the line 2-2 of Fig. 1, but on a larger scale.

Fig. 3 is a diagram indicating a modification of the invention. Referring now more specifically to the main figures, 10 indicates a valve casing introduced into or constituting a part of a stand pipe in which water under pressure is presumed to be maintained but through which the water is adapted to flow as a result of a break or outlet at any point in the system beyond said casing, the direction of the flow being indicated by an arrow. With- 1n the casing 10 is a movable valve 11 pivoted at 12 and normally held seated closed, as shown in full lines, by the superior pressure of the water on the side of the valve having the larger surface or this su erior pressure on the valve may be produce by a spring 13 or anyl other well known means tending to close t e valve. Except that there is cast or otherwise formed on the valve a lug 14, the valve may be presumed'to be of conventionalconstruction as well as action. The lug is so formed as to project in a direction remote from the pivot 12.

Extending downward or laterally from the casing is a neck 15, and connected to said neck by any suitable means is a neck por-' tion 16 of a switch casing 17 which except as otherwise about to be described is filled nism and which opening is sealed b means of a plate or cover 18 to which e neck 16 is attached. One end of the casing 17 is closed by means of a plug 19 constituting one of the principal parts of my improved switch. The outer end of the plug If.) is formed rectangular at 20 for the manipulation of the plug by means of a wrench or the like.

This plug 19 and its extension 20 are bored or otherwise formed with ports 21 and 22 at right angles with each other, the port 21 being longitudinal or parallel to the ax s of the casing 17, while the port 22 is horizontal and transverse. Communicating with the latter port are two parallel upri ht ports 23 extending from the upper sur ace of the squared portion 20. Tapped 1nto or otherwise secured in communication with the upright ports 23 are a pair of nipples 24, into the upper end of each of which is secured one free terminal of an insulated conductor 25, the connection between the terminal and the nipple being shown as effective through a packing gland 26. The free ends of the terminals 25 are secured thus at the same level within the nipples.

27 indicates'a bent flexible resilient tube located within the switch casing 17 and having one end secured, as by means of a coupling nipple 28, to the port 21. This tube 27 is shown bent twice upon itself formin upper, lower, and intermediate legs, eac connected to the next by means of a half circular bend. To the remote end of the uppermost leg of the tube is secured a coil spring 29 shown in the main figure as constit-uting a tube extending through the end portion of the casing 17 remote from the plug 19 and constituting an air vent. The spring tube 29 is sealed in the casing 17 by means of a nipple 30 and gland 31. The outer open free end of the spring tube 29 projects upward to any convenient level above the other parts of the switch mechanism. The two tubes 27 and 29 are connected to each other in open communication within a T-shaped coupling member 32, the coupling member havin a boss 33 in line with the axis of the nec s 15 and 16 and in which is fixed a rigid arm 34 havin normal contact with the valve lug 14. hile the normal operative osition of the parts is that indicated in ig. 1 in full lines, the closed valve is holding the three legs of the tube 27 substantially parallel and horizontal. When the valve 11 opens as a result of a flow of water the lug 14 releases its contact with the free end of the arm 34, setting the switch tube 27 free to assume the position shown in dotted lines due to the resiliency of said tube and that of the spring 29. The uppermost and intermediate legs at least of the tube 27 will be elevated to or toward the cover plate 18'of the switch casing.

It being borne in mind that the interior of the tubes 27 and 29 is hermetically sealed from the water contained in the casing 17, the tube 27 is filled with any suitable movable or fluid contact medium Hg up to about the level of the upper half-circular bend 35 which normally is about the level of the centers of the nipples 24. This medium is indicated as mercury and with its surface spaced just below the terminals 25. When t e valve 11 opens and the position of the upper legs of the tube 27 shifts u ward as before stated, the contact medium g flows downward by gravity to about the level indicated by the dottel line a, and so while the actual level of the medium is raised in the tube a sufiicient quantity of said medium will be raised in the ports 23 to touch the terminals 25, thereby closing the circuit from one terminal to the other through that portion of the medium in the nipples 24 and plug extension. When the valve is closed again the lug 14 strikes against the free end of the arm 34 and moves it back to normal position and consequently brings the switch to its normal open osition automatically. While I have prove by numerous experiments that the device is both sensitive and thoroughly reliable either with or without the air vent at 29, I find that the action is a little more satisfactory with the air vent employed. While I have indicated the automatic switch mechanism as applied to a horizontal stand pipe it is ObVlOUS that by any convenient slight variation in connections the same may be adapted to a stand pipe having any other di ition.

In the modification of Fig. 3, 10 indicates a boiler or other container for a body of water the level of which is to be maintained a proximately constant. Fitted in any suita le part of this boiler about the water level is a switch casing 17 having an extension 20 with ports as above described in connection with Figs. 1 and 2 for the connection of contact terminals 25. A resilient tube 27' is fixed in the port 21 and filled with mercury up to about the level heretofore described. To the uppermost leg of the tube 27 is fixed a ball float 34 which acts in the usual manner in conjunction with the water level. When the water level is at its normal and the ball 34' is sustained thereby as intended the level of the mercury in the bent portion of the tube is just below the terminals 25. lVhen however the level of the water in the boiler falls below what it should be the ball 34 naturally falls and causes or permits the swinging of the upper parts of the tube 27' in about the manner indicated by the dotted lines of Fig. 1, causing the effective level of the mercury to rise in the extension 20 closing the circuit and giving the alarm or indication to the intended person or ofiicial, or possibly for the setting into operation automatically of suitable mechanism, not shown, for replenishing the supply of water in the boiler bringing it up to the intended level and with the result that the switch will again be opened at the terminals 25.

I claim:

1. In automatic switch mechanism for sprinkler systems or the like, a water tight casing, a flexible tube Within the casing, the tube being bent upon itself and filled with a movable contact medium normally up to the bend, a pair of spaced contacts associated with but normally spaced from said contact medium, and means acting upon the tube to so change its position as to cause the level of the contact medium to move downward relatively from its normal position at the bend and thereby cause the circuit to be closed through said normally spaced con tacts.

2. In automatic switch mechanism for s )rinkler systems or the like, a. casing, a resilient tube fitted at one end in one end of said casing, said end of the casing being provided with a pair of horizontal ports communicating with each other and one of them with the end of said tube and also having a pair of vertical ports communicating with the other of said pair of horizontal ports, circuit terminals fitted in said vertical ports, a contact medium partially filling said tube and extending normally upward close below the ends of said terminals, and means con-- nected to another portion of said tube to cause movement thereof and the level of the contact medium therein, substantially as set forth.

3. In automatic switch mechanism, the combination of a switch casing, a pair of contact terminals fitted into one end of said casing on the outside thereof, a resilient tube normal level just below the contact terminals at the bend of the tube, and means acting upon the tube to cause the level of the fluid therein to drop relatively at said bend and to rise and close the circuit between said terminals.

4. A device as set forth in claim 3 in which the tube is bent twice upon itself forming a plurality of legs normally substantially parallel to one another and the contact fluid fills both of the lowermost legs.

5. A device as set forth in claim 3 in which the tube is bent twice upon itself forming three straight portions, each connected to the next by a curved bend, the contact fluid filling the tube up to the upper bend, and the means acting upon the tube to shift the levelof the fluid is connected to the uppermost leg causing the same to rise while the upper surface of the fluid moves relatively downward toward the second leg.

In testimony whereof I afiix my signature.

PATRICK A. FRIEL. 

